The present invention is directed to medical systems, and more specifically, to systems, apparatus and methods for limiting the re-usage of medical probes, such as catheters and surgical probes.
Catheters, surgical probes and related probe devices (collectively referred to, hereinafter, as xe2x80x9cmedical probesxe2x80x9d or xe2x80x9cprobesxe2x80x9d) are used today in diagnostic and therapeutic medical procedures that require surgical or minimally invasive access to target tissue areas within interior regions of the body. During these procedures, a physician locates the distal end of the medical probe at the target site by, in the case of a catheter, steering the medical probe through a main vein or artery (typically, the femoral vein or artery), or, in the case of a surgical probe, advancing the medical probe through the surgical opening leading to the target site.
The physician then operates the medical probe to activate a functional component mounted at the probe distal end, thereby providing therapeutic treatment to and/or diagnosis of the interior region. Due to the potential of passing any of a variety of dangerous diseases from one patient to another, prudent consideration dictates that the re-use of such probes should be prevented or, at the least, minimized. Typically, medical probes that are re-used are sterilized between uses to kill any disease-causing agents and to remove any tissue that has collected on the medical probe during the previous use. Sterilization of used medical probes, however, is not fool-proof, and oftentimes ineffective when tissue located on the medical probe is not exposed to the full effect of the sterilization process. Thus, even a sterilized medical probe may pose a threat to patients.
Minimizing re-use of medical probes that provide therapy becomes even more critical. During the therapeutic process, it is important for the physician to control the therapeutic component at the probe distal end carefully and precisely, so that adverse damage to a therapeutic component of the medical probe does not occur. Sterilization of and re-use of therapeutic medical probes subjects the therapeutic component to mechanical, chemical and/or thermal stress, thus jeopardizing the control that the physician may have of the therapeutic component.
The need for careful and precise control over a therapeutic medical probe is especially critical during procedures that ablate tissue within the heart. These procedures, called electrophysiological therapy, are becoming more widespread for treating cardiac rhythm disturbances. When inside the desired chamber of the heart, the physician manipulates a steering mechanism to place one or more electrodes located at the distal end of the medical probe into direct contact with the heart tissue to be ablated. The physician then directs radio frequency energy from the electrodes through the tissue to an indifferent electrode, thereby ablating the tissue and forming a lesion. If the electrodes or the electrical wires connected thereto are worn or faulty, however, ablation may be ineffective and, in the worst case, may cause charring of the heart tissue.
Preventing or limiting re-usage of medical probes, while still allowing legitimate use of these probes, is made difficult by a possible scenario wherein the physician uses the medical probe, temporarily disconnects the probe from the control unit, and reconnects the probe to the control unit to continue the procedure. Thus, there is a danger of deeming the continued procedure to be re-usage of the medical probe, which may result in the probe being rendered prematurely inoperable.
Thus, it would be desirable to provide an improved medical system for minimizing the re-usage of medical probes, while still allowing legitimate use of these probes.
The present invention is directed to improved apparatus and methods for limiting the usage of medical probes, such as, e.g., catheters and surgical probes.
In a preferred method performed in accordance with a first aspect of the invention, usage of a medical probe having an electronic storage component for storing a probe identification code is limited by determining if the medical probe has been previously used and disabling the electronic storage component if the medical probe is determined to have been previously used. The probe identification code can be any indicator that identifies a particular aspect of the medical probe, such as, e.g., a serial number or a functional or physical characteristic of the medical probe. Disablement of the electronic storage component can be effected by any means that alters the output of the electronic storage component in a manner that indicates to a control unit, such as, e.g., an RF generator, that the medical probe should not be operated.
By way of non-limiting example, the electronic storage component can be disabled by modifying the probe identification code stored in the electronic storage component, such as, by clearing the probe identification code, or by modifying the functioning of the electronic storage component, such as by shorting the output of the electronic storage component. Determination of the previous usage of the medical probe is based on an elapsed time since an initial operation of the medical probe, and/or a number of times the medical probe has been operated, and/or a previous operation of the medical probe and a sterilization of the medical probe.
In an embodiment constructed in accordance with another aspect of the invention, a medical probe comprises an elongate member, an electronic storage component having stored therein a probe identification code, and disabling circuitry electrically coupled to the first electronic storage component, wherein the disabling circuitry is configured for detecting whether the medical probe has been previously used, and for disabling the electronic storage component if the medical probe is determined to have been previously used.
By way of non-limiting example, the electronic storage component comprises one or more resistors. The electronic storage component can, however, include any non-volatile component, such as, e.g., a microchip, that can store a probe identification code. The disabling circuitry can disable the electronic storage component by shorting the electronic storage component. The disabling circuitry detects whether the medical probe has been previously used by sensing disable signal that is transmitted thereto from an external source, such as, e.g., a control unit. Alternatively, the disabling circuitry can internally determine whether the medical probe has been previously operated by means, such as, e.g., detecting an elapsed time since an initial operation of the medical probe, and/or a number of times the medical probe has been operated, and/or a previous operation of the medical probe and a sterilization of the medical probe.
In another embodiment constructed in accordance with still a further aspect of the invention, a control unit for connection to a medical probe having an electronic storage component for storing a probe identification code, comprises control circuitry electrically coupled to the electronic storage component for determining if the medical probe has been previously used, and for disabling the electronic storage component if the medical probe is determined to have been previously used.
By way of non-limiting example, the control circuitry is a microprocessor and disables the electronic storage component by modifying the probe identification code stored in the electronic storage component, such as, by clearing the probe identification code, or by modifying the functioning of the electronic storage component, such as by shorting the output of the electronic storage component. Determination of the previous usage of the medical probe is based on an elapsed time since an initial operation of the medical probe, and/or a number of times the medical probe has been operated, and/or a previous operation of the medical probe and a sterilization of the medical probe. The control unit further comprises an RF power source, and an interlocking device electrically coupled between the RF power source and the microprocessor for preventing operation of the medical probe upon receipt of an interlocking control signal from the microprocessor.
In accordance with still a further aspect of the invention, a medical probe system comprises a medical probe carrying an electronic storage component storing a probe identification code, and a control circuit electrically coupled to the electronic storage component, wherein the control circuit is configured for determining if the medical probe has been previously used, and for disabling the electronic storage component if the medical probe is determined to have been previously used.
By way of non-limiting example, in a preferred embodiment of the medical probe system, the control circuit disables the electronic storage component by modifying the probe identification code by means, such as, e.g., clearing the probe identification code. The medical probe system further comprises disabling circuitry electrically coupled between the electronic storage component and the control circuit. The control circuit is configured for transmitting a disable signal to the disabling circuitry when the medical probe is determined to have been previously used, such disabling circuitry disables the electronic storage componentry, by means such as, e.g., modifying the functioning of the electronic storage componentry or modifying the probe identification code.
Other and further objects, features, aspects, and advantages of the present invention will become better understood with the following detailed description of the accompanying drawings.